CVE-2026-53090: Linux kernel · bpf: Fix ld_{abs,ind} failure path analysis in subprogs
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 7.8 High · fixed in ee861486e377edc55361c08dcbceab3f6b6577bd : patch Linux kernel soon.
Data as of 26 Oct 2026, 14:18 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 3% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Total control over the software or total information disclosure
CISA SSVC assessment, 2026-10-16.
- Patch
- Available – fixed in ee861486e377edc55361c08dcbceab3f6b6577bd, de1055e7f9e67af32b1f3376066272b04e5223c0, d846d83bdacbd8f14fc45c63b8c1d22608452e1c +5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 24 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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Description
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix ld_{abs,ind} failure path analysis in subprogs Usage of ld_{abs,ind} instructions got extended into subprogs some time ago via commit 09b28d76eac4 ("bpf: Add abnormal return checks."). These are only allowed in subprograms when the latter are BTF annotated and have scalar return types. The code generator in bpf_gen_ld_abs() has an abnormal exit path (r0=0 + exit) from legacy cBPF times. While the enforcement is on scalar return types, the verifier must also simulate the path of abnormal exit if the packet data load via ld_{abs,ind} failed. This is currently not the case. Fix it by having the verifier simulate both success and failure paths, and extend it in similar ways as we do for tail calls. The success path (r0=unknown, continue to next insn) is pushed onto stack for later validation and the r0=0 and return to the caller is done on the fall-through side.
References
- git.kernel.org/stable/c/928d354ae3557e8f755a227e67be88034eb3cd7f (opens in a new tab)
- git.kernel.org/stable/c/8a800497d9f6c2ec9c2c1ba7b71d0ac2ea7f7bbe (opens in a new tab)
- git.kernel.org/stable/c/de1055e7f9e67af32b1f3376066272b04e5223c0 (opens in a new tab)
- git.kernel.org/stable/c/37ad2bb11e9de92cb7b94548705eeedd87f7d392 (opens in a new tab)
- git.kernel.org/stable/c/8674e2db06cff6b50f2216eed9a761d15425bb34 (opens in a new tab)
- git.kernel.org/stable/c/ce01a4e5cfac7adbe0be565f90cd32ecbb2f8337 (opens in a new tab)
- git.kernel.org/stable/c/d846d83bdacbd8f14fc45c63b8c1d22608452e1c (opens in a new tab)
- git.kernel.org/stable/c/ee861486e377edc55361c08dcbceab3f6b6577bd (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-53090 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2492305 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-53090.json (opens in a new tab)